This research program has been directed at the following goals: A) using the chemical agents alloxan and ninhydrin as possible probes for determining the presence of glucoreceptors in beta cells; B) applying computer-aided steric and structural analysis to test and design analogues of D-glucose, alloxan, ninhydrin, and related agents for evaluating insulin release activity, in vitro; C) extending biochemical investigations using a plasma membrane preparation from isolated islets to study membrane processes, i.e., receptor, radioligand binding, and enzymatic activities related to insulin release; D) characterizing the role and regulation of polymerized and depolymerized tubulin and microfilaments in glucose-induced insulin release; and E) identifying calcium-dependent regulator protein (CDR) sensitive processes in islets, i.e., protein phosphorylation and Ca-Mg ATPase activity.